During the 1970s and 1980s, the tiny Pacific island country Nauru had one of the highest gross domestic products per capita in the world thanks to its massive phosphate deposits. Its phosphate, a key ingredient in fertilizer, comes from accumulated bird droppings.

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Why Is Bird Poop White?

Actually, bird poop, per se, is not white. Birds, unlike mammals, do not have separate exits for urine and feces. Both waste products are eliminated simultaneously through the cloaca. While mammals excrete nitrogenous wastes mostly in the form of urea, birds convert it to uric acid or guanine,